Syringe barrel and cylinder holder

ABSTRACT

An arcuate guide projection is provided on a front surface of a flange of a syringe barrel and an arcuate guide groove for guiding the guide projection is provided on a front sidewall surface of a flange insert groove of a cylinder holder. When the syringe is mounted, the guide projection and the guide groove are brought into engagement thereby preventing the flange from slipping off upwardly.

[0001] This is a divisional of U.S. application Ser. No. 10/211,099filed Jul. 31, 2002.

FIELD OF THE INVENTION

[0002] The present invention relates to a syringe and a cylinder holderwhich are suitable for injection at high injection pressure using adriving mechanism such as an automatic injection device.

DESCRIPTION OF THE RELATED ART

[0003] Syringes are used for injection of liquid in various fieldstypically including a medical field. Injection of a chemical solutionhaving high viscosity such as a contrast agent for X ray CT imaging anda contrast agent for MRI (magnetic resonance imaging apparatus) requireshigh pressure, causes difficulty in manual handling, and makes intensejobs. Therefore, it is general to effect injection using a mechanicalsyringe driving mechanism such as an automatic injection apparatus andthe like. FIG. 13 shows a syringe 20 to be mounted on such an automaticinjecting apparatus 10. The automatic injecting apparatus 10 comprises acylinder holder 11, a piston holder 12, and a motor inside (not shown),and the cylinder holder 11 fixes a syringe barrel 21 by holding a flange22 and the piston holder 12 holds a piston flange 24. A piston 23 can bemoved relative to the syringe barrel 21 by progressing or regressing thepiston holder 12 by a motor, to effect injection (discharge of liquidfrom the syringe) or suction of liquid. FIG. 14 shows the syringe 20mounted on the automatic injecting apparatus 10.

[0004] Further, as shown in FIG. 15, when a syringe of smaller size ismounted on this automatic injecting apparatus, the syringe barrel 21 ismounted on a dismountable adaptor 13 (functions as a cylinder holder forthe syringe) which is further mounted on the automatic injectingapparatus 10. FIG. 16 shows the syringe 20 mounted on the automaticinjecting apparatus 10.

[0005]FIG. 18 provides detailed drawings of the adaptor 13 ((a) is aplan view, and (b) is a rear side view)). The syringe barrel 21 can beheld by fitting the flange 22 of the syringe barrel 21 into a flangeinsertion groove 14 of the adaptor 13. For the mounting, as shown inFIG. 17(a), the flange 22 is fitted into the flange groove 14 whiledirecting a flange cut portion 25 vertically. Then, the flange isrotated by 90° to be fixed so that it is not disconnected. FIG. 17(b) isa view showing the rotating process, and FIG. 17(c) is a view showingthe use position.

[0006] In the operational position, the arc of the flange is engagedwith the arc of the flange insert groove so as not to slip off in theupward direction. However, to prevent the slip-off, it is necessary tosecure a certain level of the arc length of the flange insert groove andtherefore the opening length of the flange insert groove cannot be madelarge. At the time of mounting the syringe, if the difference betweenthe opening length L′ and the length of the flange cut part W can not bemade large as shown in FIG. 17(a), the mounting operation will need timeand effort.

[0007] Further, the flange thickness and the flange insertion groovewidth are so designed to give slight clearance between the flange andflange groove for enabling smooth mounting of the syringe barrel. Thereason for this design is also that if the clearance is designed to zerocompletely, mounting may be sometimes impossible due to certain extentproduction error to be taken into consideration because the syringebarrel and the cylinder holder (including the adaptor) are usuallyformed of different materials. Consequently, slight backlash and play inmounted condition is inevitable. However, if there is an error in themounting procedure, the syringe may sometimes be raised from the rightposition. If injection of a contrast agent and chemical solution isconducted when fitting in such slight clearance is displaced, the pistonshall be pushed under condition in which the flange 22 is inclinedrelative to the flange insertion groove 14, as shown schematically inFIG. 19, and the total pressure is concentrated only on a part of theflange, and resultantly, in the worst case, the flange may beoccasionally broken particularly from the base part.

SUMMARY OF THE INVENTION

[0008] The present invention has been achieved in view of the abovedescribed problems, and its object is to provide a syringe barrel acylinder holder, where the syringe is not easily broken in injectingliquid of high viscosity at high pressure and can be easily mounted.

[0009] An aspect of the present invention is directed to a syringebarrel, comprising a guide projection on a front surface of a flange.

[0010] The syringe barrel may further comprise a press projection formedon the rear surface of the flange; a tip of the press projection beingcapable of compressed to press the flange against a front sidewallsurface of a flange insert groove when the flange is inserted into theflange insert groove formed in a cylinder holder and is fitted in a useposition.

[0011] Another aspect of the present invention is directed to a cylinderholder for holding a syringe barrel having a flange, the syringe barrelcomprising a guide projection on a front surface of the flange, thecylinder holder comprising: a flange insert groove for holding a flangeof a syringe barel and a guide groove formed on a front sidewall surfaceof the flange insert groove; the guide groove being capable of guiding aguide projection formed on a front surface of a flange of a syringebarrel.

[0012] In the present invention, the guide projection is preferablyformed in arcuate shape. Also, the guide groove is preferably formed inarcuate shape. “Arcuate shape” generally means that at least a portionof one line of outward form is a part of a circle. In the preferredembodiments, portions of two lines opposite to each other are the partsof concentric circles. The examples will be described by showing theembodiments.

[0013] The above-mentioned syringe barrel and the above-mentionedcylinder holder may be used in combination for a chemical solutioninjection system.

[0014] The above described syringe barrel may be used in combinationwith a syringe piston for a pre-filled syringe filled with a chemicalsolution. The chemical solution may include a contrast medium.

[0015] In the present invention, the term “cylinder holder” means onewhich can hold a syringe barrel by a groove, and when a syringe barrelis mounted on an adaptor before being set in an injecting apparatus, theterm “cylinder holder” is construed to include such adaptor. Thecylinder holder is usually incorporated in an automatic injectingapparatus, or integrated with an automatic injecting apparatus as onebody.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 shows the state in which a syringe barrel is mounted on acylinder holder.

[0017]FIG. 2 shows an adaptor (cylinder holder), wherein (a) is a planview from a mounting direction of the syringe, and (b) is a side crosssectional view in which an A-A cross section of (a) is seen from rearside.

[0018]FIG. 3 is a cross sectional view of a flange insert groove of anadaptor.

[0019]FIG. 4 is a side view of the flange surface of a syringe barrelseen from a front side, wherein

[0020] (a) shows a frontal view (whole view) of the flange, and

[0021] (b) shows an enlarged view of part B of (a).

[0022]FIG. 5 is a cross sectional view of a syringe, wherein

[0023] (a) shows an F-F cross section of FIGS. 4 and 11,

[0024] (b) shows a C-C cross section of FIG. 4 and an E-E cross sectionof FIG. 11.

[0025]FIG. 6 schematically shows the state of mounting a syringe on anadaptor, wherein

[0026] (a) shows a state before mounting, and

[0027] (b) shows a state after mounting, of being rotated partway to afixing location.

[0028]FIG. 7 shows a comparison between an opening length of an adaptorof the present invention and that of a conventional one, wherein

[0029] (a) shows an adaptor of the present invention, and

[0030] (b) shows a conventional adaptor.

[0031]FIG. 8 shows an embodiment of the syringe of the presentinvention, wherein

[0032] (a) is a side view of the syringe, and

[0033] (b) is a rear view of the flange seen from rear side the syringe.

[0034] FIGS. 9(a) and (b) show examples of the press projection.

[0035]FIG. 10 shows the state in which a flange is inserted into aflange insert groove and fixed.

[0036]FIG. 11 is a front side view to show a flange surface of adifferent example of the syringe barrel, wherein

[0037] (a) is a front view (whole view) of the flange, and

[0038] (b) is an enlarged view of the part D of (a).

[0039]FIG. 12 shows a different example of the adaptor (a cross sectioncorresponding to the A-A cross section of FIG. 2).

[0040]FIG. 13 shows a state of mounting a syringe on an automaticinjection device.

[0041]FIG. 14 shows a state of a syringe which is mounted on anautomatic injection device.

[0042]FIG. 15 shows a state of mounting a syringe on an automaticinjection device using an adaptor.

[0043]FIG. 16 shows a state of a syringe which is mounted on anautomatic injection device.

[0044]FIG. 17 schematically shows holding and positioning of a syringeby means of the cylinder holder (adaptor) of the automatic injectiondevice shown in FIGS. 13 and 15.

[0045]FIG. 18 is an enlarged view of an adaptor.

[0046]FIG. 19 schematically shows a state in which the flange of asyringe barrel is displaced floating up from the cylinder holder.

DESCRIPTION OF SYMBOLS

[0047]10 . . . automatic injection device

[0048]11 . . . cylinder holder

[0049]12 . . . piston holder

[0050]13 . . . adaptor

[0051]14 . . . flange insert groove

[0052]21 . . . syringe barrel

[0053]22 . . . flange

[0054]23 . . . piston

[0055]24 . . . piston flange

[0056]25 . . . flange cut part

[0057]31 . . . syringe barrel

[0058]32 . . . flange

[0059]33, 33 a, 33 b . . . guide projection

[0060]34, 34 a to 34 d . . . guide projection

[0061]40 . . . adaptor

[0062]41 . . . guide groove

[0063]42 . . . guide groove

[0064]51 . . . press projection

[0065]52 . . . reinforcing rib

[0066]52 a . . . radial part of reinforcing rib

[0067]52 b . . . concentric part of reinforcing rib

DETAILED DESCRIPTION OF THE INVENTION

[0068]FIG. 1 shows the state in which a flange 32 of a syringe barrel 31is fitted in a flange insert groove 14 of an adaptor 40 (cylinderholder). FIG. 2 shows the adaptor 40 in which FIG. 2(a) is a plan viewseen from an attaching direction of the syringe barrel and FIG. 2(b) isan A-A cross section in FIG. 2(a) viewed from rear side. FIG. 3 is anenlarged cross sectional view of a portion of the flange insert groove14. A guide groove 41 is formed in an arcuate shape on a front sidewallsurface of the flange insert groove 14 provided in the adaptor.

[0069] In the meantime, FIG. 4 shows the flange of the syringe barrel,which is used together with the adaptor, viewed from the tip side of thesyringe ((a) is a whole view of the front surface and (b) is an enlargedview of the part B of (a)). As shown in this drawing, the front surfaceof the flange 32 is provided with arcuate guide projections 33 (33 a, 33b). An F-F cross section of FIG. 4 is shown in FIG. 5(a), and a C-Ccross section in FIG. 5(b). As shown in the cross sectional view of FIG.5(a), the guide projection 33 of this embodiment has a cross sectionshape in accordance with the guide groove 41 of the adaptor and anarcuate shape in the lengthwise direction, and is adapted to be able torotate along the guide groove 41 of the adaptor. It is preferable toform the end portion of the guide projection in a longitudinal directionin a tapered shape as shown in FIG. 5(b) so as to be smoothly guidedinto the guide groove.

[0070]FIG. 6 is a cross sectional view of the flange insert groove seenfrom rear side showing the mounting of the syringe barrel onto theadaptor. First, as shown in FIG. 6(a), the flange 32 is inserted intothe flange insert groove 14 while keeping the flange cut part 25substantially vertical. Thereafter, as shown in FIG. 6(b), the guideprojection 33 is rotated while being fitted in the guide groove 41 untilit reaches the use position.

[0071] Referring to FIG. 7, the opening length of the flange groove willbe described. FIG. 7(b) is a conventional adaptor; since it has no guidegroove, the arc part of the groove needs to be made large to prevent theflange from slipping out upwardly. For this reason, the opening L′ canonly be slightly larger than the length of the flange in the flange cutpart direction W (see FIG. 17). On the other hand, since the adaptor ofthe present invention shown in FIG. 7(a) can prevent the upward slip offwith the guide groove 41, the arc part of the groove can be made short.As a result, the opening length L can be made large and therebyfacilitating the mounting operation of the syringe. As a matter ofcourse, the adaptor of the present invention may be arranged such thatthe length of the arc part of the flange insert groove is as long asthose of conventional types to prevent the slipping off of the syringemore securely. But, for general uses, it is preferable to make theopening length large placing higher priority on the operationalconvenience and workability.

[0072] There are no particular restrictions on the cross section shapesof the guide projection and the guide groove of the adaptor as long asthey fit with each other easily and the syringe will not slip offupwardly. In the case of the trapezoidal cross section shape shown inFIG. 5(a), for example, arrangement may be such that the height h is 1to 3 mm, the bottom surface width t1 is 1 to 3 mm, and the upper surfacewidth t2 is 0.5 to 2.5 mm. The guide groove may be formed in accordancewith this shape. Also the size of guide projection in a longitudinaldirection (circumferential direction) may be conveniently made shorterthan the opening length of the flange insertion groove while keeping itwithin a range in which an upward floating up is effectively preventedwhen the syringe is mounted. For example, for a syringe barrel with anouter diameter of 30 to 40 mm, the size of guide projection in alongitudinal direction may be 20 to 120 degrees, and preferably 30 to 90degrees in terms of angles taking the center of barrel as the center ofangle.

[0073] Although the cross section is a trapezoid in this embodiment, itmay be a square, a triangular, or etc.

[0074] Preferably, in the present invention, the rear surface of theflange is provided with a press projection. Also in the presentinvention, by providing a reinforcing rib on the rear surface of theflange, the breakage of the flange may further prevented.

[0075]FIG. 8 shows an example of the flange 32 having press projections51 and reinforcing ribs 52. When the flange is fitted in the useposition by inserting it into the flange insert groove, the tip of thepress projection is compressed generating elastic force to press theflange forwardly, and thus the flange is firmly secured. As shown inFIG. 9(a), the press projection 51 preferably has a narrower widthtoward the tip to make it more easily deformed by being pressed. Theouter cylinder of the syringe is generally formed of a resin such aspolypropylene, and the adaptor is formed of ABS, polycarbonate, or thelike. Depending on the selection of the material, the cylinder holderside may be arranged to be compressible. When the above describedmaterials are used, the projection of the syringe barrel is compressed.At this moment, even if the tip of the projection undergoes plasticdeformation by compression, a certain level of the compressive force ispreserved and therefore the flange is firmly secured by the resiliency.

[0076] The shape and the height of the projection may be determinedtaking these materials into account. Generally, it is preferable toarrange such that the distance from the front surface of the flange tothe tip of the press projection is larger than the width of the flangeinsert groove by about 0.1 to about 2.5 mm, more preferably about 0.2 toabout 1.0 mm. The press projection may have a conical shape as shown inFIG. 9(b).

[0077]FIG. 10 shows the state in which the flange 32 is fitted in theflange groove. The press projection 51 has undergone deformation,thereby pressing the flange 32 against the front surface of the flangegroove 14. The position of disposing the press projections 51 is, asshown in FIG. 8, preferably a position close to the back side of theguide projection 33 formed on the front surface of the flange.

[0078] There are no particular restrictions on the shape of thereinforcing ribs, and an example may include a combined shape of aconcentric part 52 b and a radial part 52 a as shown in FIG. 8. In thisexample, since the press projections 51 are formed on the extension ofthe radial part, the radial part is deformed accordingly. The pressprojection may be arranged in other places.

[0079] Next, other embodiments of the guide projection will be shown.

[0080] In the example shown in FIG. 11, a guide projection 34, which isshorter than the guide projection shown in FIG. 4, is formed in fourplaces. As shown in the enlarged view of FIG. 11(b), the end-to-enddistance including adjacent two guide projections 34 a and 34 b ispreferably arranged in the same manner as the length of the guideprojection 33 in the lengthwise direction shown in FIG. 4. The E-E crosssectional view is the same as the one in FIG. 5, and arrangement may bemade in the same manner as the example of the guide projection of FIG.4. In FIG. 11, an example is shown in which a press projection andreinforcing ribs are formed on the rear surface.

[0081] The guide projection may be of a plurality of truncated conesplaced in a line in the circumferential direction; in which case, aplurality of truncated cones may be disposed at the positions where theguide projections of FIG. 4 are provided.

[0082] As described, in a preferable embodiment of the presentinvention, the number of the arcuate guide projections may be evennumber and each half number is symmetrically positioned on the flangewhere the two flange cut portions are not provided.

[0083] Although, in the above described examples, the guide projectionis formed on each side of the flange cut part (top and bottom in FIGS. 4and 11), it may be formed on only one side. The guide groove of theadaptor to be used in combination with the guide projection may be openin the top part as with the guide groove 41 shown in FIG. 2 or closed aswith the guide groove 42 shown in FIG. 12. When the top part is closed,the flange can be inserted into the adaptor keeping its guide projectiondown, and then be rotated until the use position is reached.

[0084] The above-described embodiment is one example of the presentinvention, and it should be noted that various changes can be madewithout departing from the scope of the present invention.

[0085] As described above, according to the present invention, there canbe provided provide a syringe barrel a cylinder holder, where thesyringe is not easily broken in injecting liquid of high viscosity athigh pressure and can be easily mounted.

What is claimed is:
 1. A solution injection system comprising: amechanical syringe driving mechanism having a barrel holder with aflange insert groove and an arcuate guide groove formed on a front sidewall surface of the flange insert groove; and a syringe having a syringebarrel comprising a barrel having a body configured to be receivedwithin said barrel holder and having a first end and a dispensing endopposite the first end, a flange extending outwardly from the barrelbody proximate said first end and having an arcuate guide projectionextending outwardly from a front surface of the flange towards thedispensing end, and wherein the arcuate guide projection is configuredto engage with the guide groove of the barrel holder when the syringebarrel is inserted into the barrel holder.
 2. A system according toclaim 1, further comprising: a press projection formed on the rearsurface of the flange; a tip of the press projection being capable ofbeing compressed to press the flange against a front sidewall surface ofa flange insert groove when the flange is inserted into the flangeinsert groove formed in a cylinder holder and is fitted in a useposition.
 3. A system according to claim 1, wherein the guide projectioncomprises two sections.
 4. A system according to claim 3, furthercomprising: a press projection formed on the rear surface of the flange;a tip of the press projection being capable of being compressed to pressthe flange against a front sidewall surface of a flange insert groovewhen the flange is inserted into the flange insert groove formed in acylinder holder and is fitted in a use position.
 5. A system accordingto claim 1, wherein the flange has two flange cut parts symmetricallypositioned in the flange opposite to each other.
 6. A system accordingto claim 5, wherein an even number of the arcuate guide projections areprovided so that each half number is positioned symmetrically to eachother on the flange where the two flange cut parts are not provided. 7.A system according to claim 6, wherein the guide projections are arcuatein shape.
 8. A system according to claim 2, wherein the press projectionhas a narrower width toward the tip, whereby the press projection iscapable of being more deformed by being pressed.
 9. A system accordingto claim 1, wherein the guide projector comprises a plurality of guideprojections aligned in a line in the circumferential direction on afront surface of the flange.
 10. A system according to claim 9, whereinthe flange has two flange cut portions symmetrically positioned in therim of the flange opposite to each other.
 11. A system according toclaim 10, wherein an even number of the guide projections in the form oftruncated cones are provided so that each half number is positionedsymmetrically to each other on the flange where the two flange cutportions are not provided.
 12. A system according to claim 1, whereinthe syringe is pre-filled with a chemical solution.